In various papers published in these Bulletins during the past five years attention has been called to the injuries caused in grass land and pastures by the numerous species of Jassidae which swarm, often by millions to the acre, upon various species of grass.

In these papers it has been shown that the loss, though seldom noticed, must be really enormous and that by the use of the tar-pan or “hopper-dozer” the insects may be to a great extent destroyed. Further than this, however, our knowledge has been too meager to furnish a certain basis for remedial measures. It is true studies were made of a few species and some facts learned as to their life-history which warranted the belief that burning, mowing or other methods more satisfactory than the tar-pan might be of service but still so much remained unknown regarding the most common species that there seemed a necessity for a more extensive study. At the beginning of the present season a study was planned, the essential features of which were: 1st, the determination of the life histories of as many as possible of the species known to feed upon grasses; 2nd, the determination of the range of food plants for each species especially in the larval stages and 3rd, the collection of all species occurring on grasses and their careful identification with a close study of the specific limits of each as a basis for further life-history studies.



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